A moist-electric generator fabricated from the multilevel porous cellulose-based aerogel enhanced by incorporating MOF-801 and conductive PEDOT:PSS

Natural cellulose aerogels with super-hygroscopicity and biocompatibility have attracted much attention in the development of moist-electric generators (MEGs) and are considered an important strategy to tackle the current energy crisis. However, conventional cellulose aerogels exhibit limited voltage output due to their intrinsic structural characteristics, which significantly restricts their practical applications. Herein, a hierarchically porous aerogel with conductive network is constructed by loading metal-organic framework 801 (MOF-801) onto a cellulose nanofiber substrate, followed by incorporation of poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). The combination of MOF-801 micropores with the macropores/mesopores of the cellulose network increases the specific surface area from 146.2 to 610.1 m 2 /g and creates abundant ionizable sites for continuous hydronium (H₃O + ) generation under humid conditions. PEDOT:PSS forms a three-dimensional percolating conductive network and introduces additional sulfonate groups, which together reduce carrier-transport resistance and couple ion and electron transport. As a result, the 10-CPM-MEG achieves an open-circuit voltage (V OC ) of 7.00 V at 85 % relative humidity (RH) and maintains a V OC of 0.52 V even at 33 % RH. Series-connected 10-CPM-MEGs can power LEDs and produce a sustained current of 0.14 μA under high-temperature steam conditions (80 °C, 90 % RH). This moist-electric energy harvesting system demonstrates significant potential for high-voltage electronics applications while providing a viable pathway for recovering low-grade thermal energy from industrial waste steam.